Cox San Diego Streamlines Phone Backbone


Cox Communications’ San Diego system replaced eight seven-foot racks of networking equipment with two high-density optical switches to connect its two primary data centers for telephone traffic.

The upgrade not only saved space, but cut power consumption, said David Vaughn, telephony-engineering manager for Cox San Diego.

“It saved us a lot of rack space, a ton of power and a ton of complexity from running copper cable everywhere,” he added.

Vaughn said installing Ciena’s CoreDirector optical switches required running only a handful of fiber-optic jumpers within each of the two data centers instead of a three-foot-thick bundle of copper cables with its previous synchronous optical networking (SONET) equipment. “You could barely reach around the bundle,” he added.

Mitch Auster, senior director of service-provider-solutions marketing at Ciena, said Cox San Diego was the first cable system to deploy CoreDirector, adding that another MSO, which he wouldn’t name, is deploying the system.

“We’re starting to see the backbones of telco and cable networks becoming very similar,” he added.

Vaughn said other Cox systems are evaluating CoreDirector, including those in Phoenix and Atlanta.

At Cox San Diego, the Ciena switches will provide the backbone for 300,000 telephone subscribers. The operator has two primary telecommunications facilities, in the north and south parts of the San Diego metro area.

About two years ago, it began looking for a replacement for its Nortel SONET equipment -- because the vendor was it phasing out -- which Cox used to interconnect the north and south metro-network rings.

The CoreDirectors provide a “super-high-dense cross-connect,” Vaughn said. Each offers 640 gigabits per second of bandwidth, of which Cox San Diego is using about 30 gbps. The two switches are linked over dense-wavelength-division multiplexing.

Vaughn and his team spent about eight months testing the units before they went live last fall. Cox San Diego is now migrating connections from the SONET rings to the CoreDirector -- a process Vaughn said is about 35% complete.

After the conversion is completed, the new switches will have freed up four racks of SONET gear and four racks of cross-connect panels for DS-3 (45 megabits per second, per connection) and T-1 (1.5 mbps per connection) lines.

Vaughn declined to provide a price tag for the project, but he said the cost of the two CoreDirectors was only slightly higher than deploying new SONET gear would have been.